Field of the Invention
The present invention relates to a multilayer ceramic capacitor and a method for manufacturing the same, and particularly to a multilayer ceramic capacitor having a small quantity of hydrogen and a method for manufacturing the same.
Description of the Background Art
A multilayer ceramic capacitor includes a layered body, which has a plurality of dielectric layers and a plurality of internal electrodes layered alternately, and a pair of external electrodes formed on a surface of the layered body to be conductively connected to the internal electrodes drawn out to the surface of the layered body. Ni-plating is applied to surfaces of the external electrodes to prevent dissolution into solder at the time of mounting. Further, Sn-plating is applied onto Ni-plating films to improve soldering performance at the time of mounting with soldering. The plating with Ni and Sn is typically formed by an electroplating method.
Japanese Patent Laying-Open No. 1-80011 discloses that a chemical reaction in a plating step generates hydrogen and the hydrogen is occluded into an internal electrode and that the occluded hydrogen gradually reduces a dielectric layer in a periphery to cause a problem such as deterioration of an insulation resistance. It also discloses that, when an internal electrode having noble metal (for example, Ag—Pd alloy) as a main component is used, the solution for the problem is to add metal (for example, Ni), which suppresses absorption of hydrogen, to the internal electrode.